Apparatus for removing chemically reactive synthetic resin components from the outlet chamber of a mixing head

Abstract

A mixing head has traces of the reactive mixture of synthetic resin components removed therefrom by insertion into a housing or rinsing flange into which a rinsing liquid, e.g. hot water, is forced via nozzles or orifices trained inwardly of the plane of the mixing head. The mixture of rinsing liquid and removed residue is passed through a bag filter in which the residue is collected and the rinsing liquid is recirculated.

We claim: 
     
       1. A device for removing droplet residues of a plastic composition formed from two chemically reactive components of a synthetic resin on a mouth of a discharge chamber of a mixing head in which a cleaning plunger is reversibly movable, said device comprising: a housing formed with an annular opening receiving said mouth of said head;   at least one inwardly directed generally radial spray nozzle formed in said housing, trained upon said mouth of said head, and lying in a plane of said mouth;   at least one conduit connected to each said spray nozzle for supplying a rinsing means for removing said residue from said head under pressure to said spray nozzle; and   a drive connected with said housing for rotating same relative to said head.   
     
     
       2. The device defined in claim 1, further comprising an outlet tube formed in said housing and communicating with said annular opening for conducting said rinsing medium and removed residues away from said head. 
     
     
       3. The device defined in claim 2, further comprising a filter positioned to receive said rinsing medium and said residues and separating said residues from said rinsing medium. 
     
     
       4. The device defined in claim 3, further comprising a collecting vessel downstream of said filter for collecting the rinsing medium from which said residues have been separated. 
     
     
       5. The device defined in claim 4 wherein said collecting vessel is formed with a settling chamber and with a pumping chamber separated from said settling chamber by an overflow weir. 
     
     
       6. The device defined in claim 5, further comprising a pump for recirculating said rinsing medium from said pumping chamber to said conduit. 
     
     
       7. The device defined in claim 5 wherein said filter is a bag filter having an open side, said tube having an annular collar forming a closure for said side and resiliently supported on said tube for closing said side when said collar is pressed thereagainst. 
     
     
       8. The device defined in claim 1 wherein said rinsing means is water. 
     
     
       9. The device defined in claim 8 wherein said rinsing means is hot water. 
     
     
       10. The device defined in claim 1 wherein said rinsing means is steam. 
     
     
       11. The device defined in claim 1 the rinsing means includes means for delivering compressed air toward said mouth of said head in said opening. 
     
     
       12. The device defined in claim 1 further comprising means for generating a negative pressure in said opening, so that said mouth of said head is subjected to suction in said opening. 
     
     
       13. The device defined in claim 1, further comprising an industrial robot engageable with said head for positioning said head in said opening. 
     
     
       14. The device defined in claim 1 wherein said housing has at least one orifice in said plane trained on said mouth of said head and provided with at least one conduit for supplying a pressurized drying gas thereto. 
     
     
       15. The device defined in claim 1, further comprising means for supplying a drying gas to said nozzle. 
     
     
       16. The device defined in claim 1, further comprising a collecting vessel downstream of said filter for collecting the rinsing medium from which said residues have been separated, said vessel being formed with a settling chamber and with a pumping chamber separated from said settling chamber by an overflow weir, and a pump for recirculating said rinsing medium from said pumping chamber to said conduit. 
     
     
       17. A method of removing droplet residues of a plastic composition formed from two chemically reactive components of a synthetic resin on a mouth of a discharge chamber of a mixing head in which a cleaning plunger is reversibly movable, said method comprising the steps of: (a) introducing said head into an annular opening formed in a housing;   (b) directing against said mouth of said head in said opening a rinsing jet of a rinsing medium from a plurality of inwardly directed generally radial spray nozzles formed in said housing and lying in a plane of said mouth;   (c) collecting rinsing medium and removed residues in a settling chamber, said rinsing medium passing over an overflow weir into a pumping chamber;   (d) recirculating said rinsing medium to said nozzles from said pumping chamber; and   (e) drying said mouth of said head by directing pressurized drying gas through at least some of said nozzles at said mouth.   
     
     
       18. The method defined in claim 17, further comprising the step of filtering the rinsing medium and said residues before said rinsing medium enters said settling chamber. 
     
     
       19. The method defined in claim 18, further comprising the step of subjecting said mouth to suction in said opening. 
     
     
       20. A device for removing droplet residues of a plastic composition formed from two chemically reactive components of a synthetic resin on a mouth of a discharge chamber of a mixing head in which a cleaning plunger is reversibly movable, said device comprising: a housing formed with an annular opening receiving said mouth of said head;   at least one inwardly directed generally radial spray nozzle formed in said housing, trained upon said mouth of said head, and lying in a plane of said mouth;   at least one conduit connected to each said spray nozzle for supplying water for removing said residue from said head under pressure to said spray nozzle;   an outlet tube formed in said housing and communicating with said annular opening for conducting said water and removed residues away from said head;   a filter operatively connected with said tube and receiving and separating said residues from said water;   a collecting vessel downstream of said filter for collecting the water from which said residues have been separated;   a pump for recirculating said water from said filter to said conduit; and   a drive connected with said housing for rotating same relative to said head.